1. Field of the Invention
The present invention relates to a power tool and more particularly, to a technique of cooling the power tool.
2. Description of the Related Art
Japanese non-examined laid-open patent publication No. 10-201205 discloses a hand-held type electric disc grinder. According to the known grinder, a cooling fan is disposed within a motor housing and driven by a driving motor. Cooling air is introduced from the rear end of the motor housing and led forward by rotation of the cooling fan. Thereafter, the cooling air is discharged to the outside from an air outlet in the vicinity of a gear housing connected to the motor housing. The flow of the cooling air cools the driving motor, the motor housing, the power transmitting mechanism and the gear housing.
While the above-mentioned cooling technique can ensure cooling performance to some degree, further improvement of the cooling effectiveness is desired.